Wing landing light



Aug. 12, 1936. s. M. FAIRCHILD WING LANDING LIGHT Filed Jan. 25. 1929 2Sheets-Sheet l Aug. 12,1930. 5. M. FAIRCHILD I WING LANDING LIGHT FiledJan. 25, 1929 2 Sheets-Sheet 2 gnvemtoz f/Mrman M78 fZl/rr/u/di PatentAug. 12, 1936 UNITED STATESL PATENT orrlcr.

SHERMAN MILLS FAIRCHILD, OF NEW YORK, N. Y., ASSIGNOB TO FAIRCHILD AVIA-TION CORPORATION, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE WINGLANDING- LIGHT 7 Application filed January 25, 1928. Serial No. 334,890.

This invention relates in general to landing lights for aeroplanes andmore particularly to lights so designed as to avoid the creation ofadded wind resistance or other dis- 6 turbing factors.

An obg'iect of my invention is to provide landing ghts to be mountedwholly within the aerofoil of an aircraft, and to provide the leadingedge of the aerofoil with an orifice covered with a section oftransparent material of suflicient area for lighting purposes and ofsuch contour as to blend perfectly with the streamline elfect of theremainder of the aerofoil.

A more particular object is to obtain the ideal projection of light barranging the light bulb at a considerab e distance rearwardly of theleading edge and b providin a reflector of such nature that t e reflectelight beams will focus at such point as to pro vide for long range lightprojection.

A further object in this connection is to provide for adjustment of thelight assembly to meet requirements in light pro'ectlon under variousapplications and con 'tions,

With the foregoing and other objects in view, the invention resides inthe combination of parts and in the details of construction hereinafterset forth, certain embodiments of the invention being illustrated in theaccompanying drawings in which:

F igure 1 is a vertical longitudinal section throu h the leading edge ofan aircraft wlng in WhlCll the light assembly is shown attached to theleading wing spar. I

Figure 2 is a front elevation of the leading edge of the wing, partlybroken away to show the sliding adjustment of the light assembly.

Figure 3 is a plan view of the light assembly with the upper covering ofthe wing removed.

Figure 4 is a diagrammatical illustration of the lamp showing the mannerof travel of the direct and reflected light beams.

Referring more particularl to the drawings, the landing light assem lyis attached by means of suitable bolts 3 to the leading spar 2 of thewing 1. The leading edge of the wing fore of the spar 2 is preferablyformed of substantially rigid material. At the extreme leading edge isformed an orifice which is covered by transparent section 4 ofrestricted area, being lesser in its vertical dimension than the leadingedge of the wing, and curved to conform to the contour of the wing, andattached to the wing by means of rivets 5. The upper surface of theleading edge is rovided with an inspection door 6 whic is provided withsuitable catches 7 normally maintained closed by the springs 8, butopened by application of hand pressureon the projection 9. A chain 10,riveted to the leadlng edge at 11 and to the inspection door at 12,serves as a means of lessening the likelihood of the door becomin lost.The transparent section 4 merely rep aces a small portion of the leadingedge and this does not 1n any way affect or alter the streamline orother aerodynamic characteristics of the wing.

.In order to obtain the desired light pro jection the lamp is placed ata point considerably istantly removed from the trans parent section 4.The lamp carrying assemblg is illustrated in Figure 1 as comprising aracketlfi bolted at 3 through the bolt holes 3' to the wing spar 2.Releasably and adjustably connected to this bracket is a sub: stantiallyconically-shaped projector, the.

same being connected screw bolt 16 and at its upper side by a similarbolt 17. The apertures 17*, 17' and 17 may be selectively engaged by thebolt 17 u on a manual tilting ad ustmentof the cone a out bolt 16 as apivot. A lamp socket 24 is conveniently arranged to receive the lamp 13lying within the principal focus of a parabolic or other type ofreflector 14 held in position by a bracket 18. The cone 19 converges sothat its forward portion practically coincides in size with that of thetransparent section 4, thus providing an initial converging of the lightbeams before they reach the transparent opening;

at its lower side by a The action of the light beams is best under ingedge of the wing, and the transparent section 4. The direct light beamsbb are shown projected through the section 4 which has been described asbeing of a restricted size. The distance of the light source and theoutlet from the wing being great, the resulting eflect will be acomparatively long range light projection.

The beams of reflected light a--a are shown as coming to a focus at X,or comparatively close to the point of outlet from the wing. Thesucceeding diverging of the reflected light beams thus starts at such apoint as to insure the maximum efficiency in light projection forairplane search lamp purposes/ The relationship of the wing, the lightorifice, the lamp, and the reflector is such that the light rays, bothdirect and reflected, are projected through the orifice in the directionof flight of the airplane.

By means of suitable adjustment of the lamp and reflector with relationto the orifice, the focus may be set at any desired distance from thewing of the plane within certain limits. In this manner a maximum oflight v is obtainable on the landing field when the aircraft is at anydesired predetermined distance therefrom.

A suitable means for tilting the lamp having been disclosed, the lampmay be adjusted forwardl or rearwardly by providing a channel beam 19bolted at 21 to the lamp carrying assembly, and by slidably mounting thechannel beam 19 on an I-beam 20 secured to any suitable longitudinalinterior win bracing member 23.

The distance between the lamp and orifice is, to a large extent, amatter of choice. The lamp could, if desired, be mounted immediatelybehind the plate 18. This, however, would necessitate the use of athicker wing, or a smaller, and less eflicient reflector. The lam too,would be very close to the wing sur ace, and might possibly damage thesame by radiated heat. For all these reasons, it is desirable to mountthe lamp some considerable distance behind the leading edge of theplane.

Another advantage of mounting the lamp some distance behind the leadingwing edge arises from the fact that, since the pencil of reflected lightH is converging, it will be the smaller, the farther from the reflector;the aperture and glass plate may then be made correspondingly smaller.In an extreme case, of course, the focus of the beam could be made topracticall coincide with the aperture, making possib e an exceedinglysmall aperture.

' It is to be understood that various changes n the construction of theembodiment illus trated in the drawings may be made without departlngfrom the spirit of the invention and it is not desired to limit theinvention to this illustration but to interpret the invention broadly inlight of the appended claims.

What I claim is:

1. The combination with an aircraft wing,

of a lamp, reflector, and a' converging cone surrounding same andcontained wholly within said wing, a light ray orifice of restrictedarea provided with a transparent covering attached to the leading edgeof said wing and of such contour as to conform with the streamlineformation of said wing, said lamp, reflector, and cone bein so arrangedas to focus the reflected light eams at a point substantiallyimmediately in front of said leading edge, said lamp, reflector, andcone being adjustable as a unit with relation to their respectivedistances from said light orifice, both horizontall toward and from saidor'ifice and pivotally a out a transverse axis.

2. The combination with an aircraft wing, of a lamp, reflector, and aconvergingcone surrounding same and contained wholly within said wing,'alight ray orifice of restricted area provided with a transparentcovering attached to the leading edge of said wing and of such contouras to conform with the stream line formation of the wing, said lamp,reflector, and cone bein arranged at a point considerably rearward ly ofsald light orifice, said lamp reflector, and cone being adjustable as aunit with relation to their res ective distances from said lightorifice, both orizontal- 1y toward and from said orifice and pivotallyabout a transverse axis.

, 3. Thecombinationwithanaircraftwing,of a lamp, a reflector, and aconverging cone surrounding same and contained wholly within said wing,a light ray orifice of restricted area provided with a transparentcovering attached to the leading edge of said wing and of such contouras to conform with the streamline formation of said wing, said lamp,reflector, and cone being so arranged as to focus the reflected lightbeams at a oint substantially immediately in front 0 said leadin edge,and means for horizontally sliding an pivotally tiltin said lamreflector, and cone as a unit for a justing t eir relation to said lightorifice.

4. The combination with an aircraft wing, of a lam a reflector, and aconver 'ng cone surroun 'ng same and containe wholly within said wing, alight ray orifice of restricted area provided with a transparentcovering attached to the leading ed e of said wing and of such contouras to con orm with the streamline formation of said wing, said lamp,reflector, and cone being so arranged as to focus the reflected lightbeams at a point substantially immediatel in front of said leading edge,and adjusta le means for varying the distances of said lamp, reflector,and a cone as a unit from said light orifice, both horizontall towardand from said orifice and pivotally a out a transverse axis.-

5. In an gglplane landing light, a source of light dispo within thewing, 'a transverse rifgid detachable section of win skin in front 0said source of light, a re ector in fixed also horizontally toward andaway from said transparent wingsection.

In testimony whereof, I have signed my name to this specification this9th day of January, 1929.

SHERMAN MILLS FAIRCHILD.

